Bruce Bolt (1930-2005) on the use of computers at the ISC

Photo of Bruce Bolt courtesy of UC Berkeley

A Personal View from Bruce Bolt

Received: October 2012

Bruce Bolt, Director of the Berkeley Seismological Laboratory for 28 years, had strong connections with the International Seismological Centre and its previous incarnation, the International Seismological Summary (ISS), not least with the introduction of the computerisation of location procedures. An article written by himself in 1994 for the Geophysical Journal International is linked below. Bolt describes his time assisting Robert Stoneley, of the Department of Geodesy and Geophysics at Cambridge University, with the production of the ISS which had been in both financial and practical difficulties with a large backlog of data to evaluate. The existing members of staff were unconvinced that Bolt’s computer program for hypocentre location would be any improvement to the conventional methods such as swing arcs on a large globe or calculations using least-squares estimates. He recalls the test of his program using an unusual event, deep beneath Spain. After an anxious wait the computer quickly provided Bolt with a solution that almost matched the one printed in the ISS. Needless to say, the program was immediately approved and put into action and the ISS swiftly made up its backlog.